package com.youth.framework.util;

import java.security.MessageDigest;

public class MD5Util
{
    
    // MD5加码。32位   
    public static String MD5(String inStr)
    {
        MessageDigest md5 = null;
        try
        {
            md5 = MessageDigest.getInstance("MD5");
        }
        catch (Exception e)
        {
            e.printStackTrace();
            return "";
        }
        char[] charArray = inStr.toCharArray();
        byte[] byteArray = new byte[charArray.length];
        
        for (int i = 0; i < charArray.length; i++)
            byteArray[i] = (byte) charArray[i];
        
        byte[] md5Bytes = md5.digest(byteArray);
        
        StringBuffer hexValue = new StringBuffer();
        
        for (int i = 0; i < md5Bytes.length; i++)
        {
            int val = ((int) md5Bytes[i]) & 0xff;
            if (val < 16)
                hexValue.append("0");
            hexValue.append(Integer.toHexString(val));
        }
        
        return hexValue.toString();
    }
    
    // 可逆的加密算法   
    public static String KL(String inStr)
    {
        // String s = new String(inStr);   
        char[] a = inStr.toCharArray();
        for (int i = 0; i < a.length; i++)
        {
            a[i] = (char) (a[i] ^ 't');
        }
        String s = new String(a);
        return s;
    }
    
    // 加密后解密   
    public static String JM(String inStr)
    {
        char[] a = inStr.toCharArray();
        for (int i = 0; i < a.length; i++)
        {
            a[i] = (char) (a[i] ^ 't');
        }
        String k = new String(a);
        return k;
    }
    
    // 测试主函数   
    public static void main(String args[])
    {
        String s = new String("1");
        System.out.println("原始：" + s);
        System.out.println("MD5后：" + MD5(s));
        System.out.println("MD5后再加密：" + KL(MD5(s)));
        System.out.println("解密为MD5后的：" + JM(KL(MD5(s))));
        System.out.println("加密的：" + KL(s));
        System.out.println("解密的：" + JM(KL(s)));
        System.out.println(MD5(s));
    }
    
}
